Zinc/air cells are typically in the form of button cells which have particular utility as batteries for electronic hearing aids including programmable type hearing aids. Such miniature cells typically have a disk-like cylindrical shape of diameter between about 4 and 12 mm and a height between about 2 and 6 mm. The miniature zinc/air button cell typically comprises an anode casing (anode cup), and a cathode casing (cathode cup). The anode casing and cathode casing typically each have a closed end and an open end. An electrical insulating material can be placed around the outside surface of the anode casing. After the necessary materials are inserted into the anode and cathode casings, the open end of the anode casing is typically inserted into the open end of the cathode casing and the cell sealed by crimping. The cathode casing can typically be of nickel plated steel or nickel plated stainless steel, for example, with the nickel plate forming the cathode casing's outside surface and stainless steel forming the casing's inside surface. The cathode casing characteristically has at least one, and more usually a plurality of small air holes in the surface at the closed end thereof. This end typically also forms the cell's positive terminal.
A removable tab can be adhered to the cell surface containing the air holes. The tab is conventionally formed of a single material, such as a plastic film which is coated on one side with a releasable pressure sensitive adhesive. The tab is pressed onto the cell surface to cover the air holes therein. The tab has a small extended portion which the user grasps by finger tip when it is desired to remove the tab from the cell. Conventional tabs are designed with the extended free portion for grasping being very small, for example, about 1/8 to 1/4 inch. It was generally thought that such small tabs are adequate. However, user satisfaction surveys conducted by the Applicant revealed that many elderly users or dexterity impaired users can have some difficulty grasping the conventional tabs. However, larger tabs if formed in the same manner as conventional tabs, are more apt to be dislodged during handling and shipment of the cells, thereby possibly causing premature activation of some of the cell.
Accordingly, it is desirable to provide removable tabs for metal/air cells, particularly miniature zinc/air cells, which tabs are easier to grasp and remove from the cell.
It is also desirable to provide removable tabs that adhere better and more uniformly to the metal/air cell surface to reduce the chance of air seepage or premature dislodgment from the cell.